Detailed Description

This is a field type class. HKey holds a key data, which represent in the sql database. The value is readed from the database, but stays read only in gSAFE. Usally holds the primary key of the sql table. Many other function search this type to identify the records to read and write,
SO IT IS STRONGLY RECOMMEND THAT EVERY SQL TABLE SHOULD CONTAIN A PRIMARY KEY (Which should be a HKey here)

Returns string format of the field's value. Very similar to getSQLValue() but the result is always acceptable in an sql varchar field. (Mostly used by the logger system, when every kind of values are stored in varchar. The gsafe try to keep the value as close to the original sql database value as possible)